Authorities in Burnsville, Minnesota, have asked residents of the city not to release goldfish into local waters. They explained the reason for their request by publishing photos of these animals.
We associate goldfish with tiny creatures swimming in miniature aquariums. But what if we let the same creatures into larger tanks? It turns out that they can grow to huge sizes. This problem was brought to the attention of the city authorities of Burnsville, who were concerned about the disturbance of the balance in the ecosystem of Lake Keller.
The city authorities explained that goldfish worsen the water quality in natural reservoirs because they uproot plants. “They grow bigger than you think,” noted the message that appeared on social media. The sizes of the individuals caught from Lake Keller were compared to balls known from American football.
Goldfish from a home aquarium usually reach about 5 cm in length. The same individual in the wild can be up to 30 cm long and weigh nearly 2 kg. Therefore, the authorities of the state of Minnesota consider them an invasive species, and releasing them into lakes and ponds is considered illegal.